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news & trends involved in materials design, such as It is a dimensionally small-but-central community leadership, data sharing, part (only 0.75 inches long with an computational validation, etc. external diameter of 0.5 inches″ and Computational According to Warren, MGI leaders an internal diameter of 0.38 inches) Tools are optimistic that the initiative will of several ovens in SAM’s Sample begin to yield benefits as early as 2013, Manipulation System, where solid with the rollout of prototype solutions phase materials are sampled by trans- and virtual communities. n porting finely sieved materials to one of Experimental Digital 74 SMS quartz sample cups. The cups Tools Data are inserted into the special oven andAdditive-manufactured ceramic heated to release volatiles. The ovens (Credit: OSTP.) heater unit playing role in Mars also help clean the cups for reuse. soil testing While one might assume that fabri- NIST released its report from May’s The work of the Mars Curiosity cating the alumina housing was simple, MGI workshop, ”Building the Materials it was not. NASA engineers designed itrover soil-sampling mission bubbled Innovation Infrastructure: Data and Standards.” up to national attention recently 52 heating elements allowing its ovento support a network of channels withwhen a NASA official touched off oritized and categorized as short-term speculation when he mentioned that capacity to reach 1,000°C. or long-term, based on whether their something “remarkable” and “for the In an email to the Bulletin, Walter impacts could make a difference in less history books” had been found. While Zimbeck, manager of TA&T’s Ceramic than five years or more than five years. it turned out that his phraseology might Micro Devices Group, described some For example, in the area of data repre- have been hyperbolic (although some of the details and considerations about sentation and interoperability, partici- proto-organic materials may have been making the oven housings via the ste- pants identified the “definition of data found), the long-distance investigative reolithography route. or metadata for particular applications work of the rover is a feat of remarkable He said that NASA selected the with standards for software to facilitate engineering, made possible with several company after finding few rapid-pro- linkage,” as both a high priority and components either from the field of totyyping suppliers able to meet their something achievable in the short term. ceramics or well-known in the ceramics specifications. “There were not any oth- The organizers of the workshop also and glass community. ers,” says Zimbeck. “Goddard did have recognized that new materials devel- For example, there is a piece of some prototypes made by plasma spray- oped in the MGI construct would be ceramic, formed by an additive manufac- ing alumina onto a mandrel and around developed with specific applications turing process—stereolithography—that pre-placed heating element wires, but in mind. Thus, they considered four is playing a significant role in the soil apparently those prototypes failed possible “technical application areas:” analysis. This piece is a custom alumina during the first heating cycle (room electrochemical storage, high-temper- ceramic heater housing produced by temperature to ~1,000°C in several ature alloys, catalysis, and lightweight Technology Assessment and Transfer minutes). The ceramic cracked, and the structural materials. They selected these Inc., a small defense and government wires broke. That’s a very challenging TAAs because, broadly speaking, they contractor based in Annapolis, Md. thermal shock event for any ceramic, represent areas that are positioned well The ceramic heater housing is an so I was actually surprised that our fully to adapt an MGI approach. Warren indispensable component of the rover’s dense high-purity alumina housings notes, however, that the four TAAs SAM (Sample Analysis at Mars) showed no signs of degradation after are only representative examples, and instrument suite. SAM’s meat-and- the first, nor after many, test cycles. workshop organizers and participants potatoes work occurs when volatile The NASA pyrolysis oven team was acknowledge that there are many other materials from the Mar soil samples elated because they were on the hook applications that could have been con- are fed into the suite’s six-column gas to provide the ovens and had no other sidered instead. chromatograph, a quadrupole mass solutions.” In both contexts, the key metric spectrometer, and a tunable laser spec- Zimbeck says the difficult part, and considered was the amount of time that trometer. the reason why no conventional pro- could be saved if the data challenges However, before the GC, QMS cesses were viable, is the high aspect were eliminated; cost issues were not and TLS can do their important work, ratio of the holes that run the length addressed directly. the soil must be prepared carefully to of the cylinders. “The inner ring of Finally, the report calls out cross- release the volatile components—and holes have a 0.008 inch diameter and cutting challenges that impact anybody that involves the ceramic heater body. are about 0.75 inches long—an aspect 6 www.ceramics.org | American Ceramic Society Bulletin, Vol. 92, No. 1


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